package com.aaa.common.utils;

import org.apache.commons.codec.binary.Base64;

import javax.crypto.Cipher;
import java.security.*;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;

@SuppressWarnings("restriction")
public class RSAUtil {

    private static final String src = "abcdefghijklmnopqrstuvwxyz";


    public static final String PUBLIC_KEY = "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCDg4aQg8KufwnX5Eu41XHRS5GfTdjZabwBpnXjKC/fv21nVvvAF96kfC/5KUAGnbYplTsjYp0idn3ecfg7I7aKlPysbC9IHz22vuXAVB0v6tSqfYbZkVyLc/OiqBJt1P/yrnms4SHRQi0wkoZdXt6Cd/CJTihJ6foBmrNqPeuXKwIDAQAB";

    public static final String PRIVATE_KEY = "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";

    /**
     * 公钥加密私钥解密
     */
    private static void test1(RSAKeyPair keyPair, String source) throws Exception {
        String text1 = encryptByPublicKey(keyPair.getPublicKey(), source);
        String text2 = decryptByPrivateKey(keyPair.getPrivateKey(), text1);


    }

    /**
     * 私钥加密公钥解密
     *
     * @throws Exception
     */
    private static void test2(RSAKeyPair keyPair, String source) throws Exception {
        String text1 = encryptByPrivateKey(keyPair.getPrivateKey(), source);
        String text2 = decryptByPublicKey(keyPair.getPublicKey(), text1);

    }

    /**
     * 公钥解密
     *
     * @param publicKeyText
     * @param text
     * @return
     * @throws Exception
     */
    public static String decryptByPublicKey(String publicKeyText, String text) throws Exception {
        X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(Base64.decodeBase64(publicKeyText));
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.DECRYPT_MODE, publicKey);
        byte[] result = cipher.doFinal(Base64.decodeBase64(text));
        return new String(result);
    }

    /**
     * 私钥加密
     *
     * @param privateKeyText
     * @param text
     * @return
     * @throws Exception
     */
    public static String encryptByPrivateKey(String privateKeyText, String text) throws Exception {
        PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(Base64.decodeBase64(privateKeyText));
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.ENCRYPT_MODE, privateKey);
        byte[] result = cipher.doFinal(text.getBytes());
        return Base64.encodeBase64String(result);
    }

    /**
     * 私钥解密
     *
     * @param privateKeyText
     * @param text
     * @return
     * @throws Exception
     */
    public static String decryptByPrivateKey(String privateKeyText, String text) throws Exception {
        PKCS8EncodedKeySpec pkcs8EncodedKeySpec5 = new PKCS8EncodedKeySpec(Base64.decodeBase64(privateKeyText));
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec5);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.DECRYPT_MODE, privateKey);
        byte[] result = cipher.doFinal(Base64.decodeBase64(text));
        return new String(result);
    }

    /**
     * 公钥加密
     *
     * @param publicKeyText
     * @param text
     * @return
     */
    public static String encryptByPublicKey(String publicKeyText, String text) throws Exception {
        X509EncodedKeySpec x509EncodedKeySpec2 = new X509EncodedKeySpec(Base64.decodeBase64(publicKeyText));
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec2);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.ENCRYPT_MODE, publicKey);
        byte[] result = cipher.doFinal(text.getBytes());
        return Base64.encodeBase64String(result);
    }

    /**
     * 构建RSA密钥对
     *
     * @return
     * @throws NoSuchAlgorithmException
     */
    public static RSAKeyPair generateKeyPair() throws NoSuchAlgorithmException {
        KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
        keyPairGenerator.initialize(1024);
        KeyPair keyPair = keyPairGenerator.generateKeyPair();
        RSAPublicKey rsaPublicKey = (RSAPublicKey) keyPair.getPublic();
        RSAPrivateKey rsaPrivateKey = (RSAPrivateKey) keyPair.getPrivate();
        String publicKeyString = Base64.encodeBase64String(rsaPublicKey.getEncoded());
        String privateKeyString = Base64.encodeBase64String(rsaPrivateKey.getEncoded());
        RSAKeyPair rsaKeyPair = new RSAKeyPair(publicKeyString, privateKeyString);
        return rsaKeyPair;
    }


    /**
     * RSA密钥对对象
     */
    public static class RSAKeyPair {

        private String publicKey;
        private String privateKey;

        public RSAKeyPair(String publicKey, String privateKey) {
            this.publicKey = publicKey;
            this.privateKey = privateKey;
        }

        public String getPublicKey() {
            return publicKey;
        }

        public String getPrivateKey() {
            return privateKey;
        }

    }
}

